With respect that's madness. The problem isn't that the player we have are rubbish as arguably a worse squad than this coasted to 7th last year. The problem is that we've signed more players than any other team in the league; regularly field at least 5/6 new signings each week; in a lineup that is constantly changing; and the poor results have dented their confidence.
Signing a bunch of new players would just make it worse imo. The team aren't a team at the moment because none of them know how the other plays. This was compounded by Koeman playing a different lineup every game, and often a different formation. The players need some consistency, both of selection and tactics.
Do that and they will improve, but it will take time. I'm almost inclined to write this season off and consider a success as bedding in a shed load of new signings, and keeping us up.